Between approximately 1930 and 1970, an Eastern public utility company installed a large number of electric meters. Many of these meters were and are still enclosed in a specific type of meter box which is commonly known as a Murray enclosure. Murray enclosures were made by Murray Manufacturing Company of Brooklyn, N.Y. A Murray enclosure has a front door which is locked closed by an interior locking mechanism known as a Metropolitan Lock.
In order to unlock the front door of the Murray enclosure, it is necessary to insert a controlled distribution, relatively large diameter, expanding key through an aperture formed in the Murray enclosure door. However, to discourage unauthorized persons from opening the Murray enclosure and tampering with the electric meter, the Murray enclosure was fitted with a glass window in the door aperture. The glass window is permanently mounted in the door aperture so that the glass window must be broken before the expanding key can be inserted. Therefore, although the glass window does not physically prevent an unauthorized person from breaking the window and opening the Murray enclosure with a pick or other burglar's tool, the broken glass does create a clear signal to the utility's inspectors that someone has tampered with the electric meter.
Not only does the glass window fail to physically prevent a thief from breaking the window and opening the Murray enclosure, but the utility's own meter installers and repairmen also must break the glass window in order to open the Murray enclosure for authorized purposes. This means that it is necessary to break the glass every time an authorized box entry is required. The resulting broken glass is dangerous and messy.
Therefore, it is an object of this invention to plug or block the keyway entrance in the door of a Murray enclosure by providing a reusable device which does not utilize glass, is not messy, and is not dangerous.
It is also an object of this invention to plug or block the Murray enclosure door aperture with a security device that physically bars the passage of an unauthorized person's pick or tools. In other words, instead of a glass window which can be easily broken by anyone, it is an object of this invention to provide a lockable plug which can be removed only by an authorized person.